1. Field of the Invention
The present invention relates to a reproducing device that extracts a necessary image from a picture stream to generate special reproduction data and so on, a medium, an information aggregate, a transmitting medium, and a recording medium.
2. Related Art of the Invention
Special reproduction such as cue and review as well as normal-speed reproduction is performed on AV data, which is recorded in a recording medium such as a hard disk and is generated based on an MPEG transport stream.
Such special reproduction is performed as follows: namely, when recording AV data in a hard disk, pointer information is prepared so as to have access to AV data used for special reproduction, and the pointer information is also recorded when recording the AV data. And then, upon special reproduction, access is made to AV data for special reproduction based on the pointer information, and an MPEG transport stream for special reproduction is generated.
In other words, when special reproduction is performed on AV data recorded in a hard disk, it is necessary to select pictures for special reproduction from AV data.
Referring to FIGS. 10 and 11, the following will describe an image processing device for generating special reproduction data. The image processing device includes a conventional reproducing device which selects pictures for special reproduction as described above from AV data recorded in a hard disk.
FIG. 10 is a block diagram showing the configuration of a conventional image processing device 80.
The image processing device 80 is configured by a readout device 88, a first converting section 83, a buffer 84, a picture processing section 85, a second converting section 86, and an output section 87.
The readout device 88 is a means of reproducing and outputting MPEG transport packets for special reproduction according to pointer information, from the DISK ACCESS UNIT configured by a plurality of MPEG transport streams to generate special reproduction data from AV data stored in a hard disk.
The first converting section 83 is a means of removing a header from a transport packet of a selected picture and making a conversion to an elementary stream.
The buffer 84 is a buffer for accumulating converted elementary streams and FIFO with a capacity for storing at least several tens of packets.
The picture processing section 85 is a means of performing processing such that a converted elementary stream matches MPEG grammar.
The second converting section 86 is a means of adding a header to a processed elementary stream and making a conversion to an MPEG transport stream.
The output section 87 is a means of outputting an MPEG transport stream for special reproduction.
Next, the following will describe the operation of the foregoing conventional image processing device 80.
FIG. 11 shows the steps of generating special reproduction data in the image processing device 80. In the image processing device 80, MPEG transport streams are converted to MPEG elementary streams, elementary streams for special reproduction are generated and accumulated in the buffer, and then, the elementary streams are converted to MPEG transport streams for special reproduction.
Namely, the readout device 88 reproduces pictures for special reproduction for each MPEG transport packet of an original MPEG2 transport stream from which special reproduction data is generated, by using pointer information recorded in a hard disk. For example, in the case where normal reproduction displays 30 pictures per second, in case of sixfold-speed special reproduction, pictures for special reproduction are selected every five pictures for each transport packet unit in a DISK ACCESS UNIT.
The first converting section 83 removes a header from a selected transport packet and makes a conversion to an elementary stream.
The buffer 84 accumulates converted elementary streams.
The picture processing section 85 performs a processing such that the converted elementary stream matches MPEG grammar.
The second converting section 86 adds a header to a processed elementary stream and makes a conversion to an MPEG transport stream.
The output section 87 outputs an MPEG transport stream for special reproduction.
As described above, the conventional image processing device 80 generates special reproduction data.
However, to generate special reproduction data, the conventional readout device 88 has access to pictures for special reproduction from MPEG transport streams for each transport packet in a DISK ACCESS UNIT. Therefore, a plurality of pictures may be included in a single transport packet.
Namely, a picture other than a picture for special reproduction may be included at the front end or the rear end of a packet. Such picture data other than a special reproduction image is displayed as image noise.
Such a problem can be solved by the picture processing section 85 according to the conventional art. However, when a transport stream is converted to an elementary stream, it is quite difficult to decide whether image data is noise or not unless the configuration of the elementary stream is carefully observed and a data size is checked.